1. Field of the Invention
This invention relates to gas transfer systems and more particularly, to a carbon dioxide fill manifold and method for using the fill manifold for handling liquid and gaseous carbon dioxide and dispensing the gaseous carbon dioxide to an end-user, such as a carbonated drink-dispensing system. The carbon dioxide fill manifold of this invention is characterized by a fill line valve attached to an atomizer and receiving a fill line for introducing liquid carbon dioxide into the atomizer, at least two liquid cylinder ports provided in the atomizer for receiving corresponding liquid chambers or cylinders and receiving and storing liquid carbon dioxide, at least one gas cylinder port also connected to the atomizer for receiving a corresponding gas cylinder and storing gaseous carbon dioxide generated in the atomizer and a gas service valve connected to the atomizer for receiving a gas service line and supplying gaseous carbon dioxide on demand to an end user. A pressure actuated valve is also provided in the atomizer between the liquid cylinder ports and the gas cylinder port(s) to facilitate automatic dispensing of liquid carbon dioxide from the liquid cylinders through the atomizer, where it vaporizes and expands into gaseous carbon dioxide for storage in the gas cylinder(s) and is ultimately dispensed to an end-user. A pressure relief valve port is also provided in the atomizer for receiving a pressure relief valve to prevent excessive system pressure in the atomizer. The carbon dioxide fill manifold is designed to handle both liquid and gaseous carbon dioxide and to provide a substantially uninterrupted supply of gaseous carbon dioxide to an end-user such as a carbonated drink dispenser, without the necessity of transporting conventional carbon dioxide pressure vessels or cylinders to and from the end-user site.
The carbon dioxide fill manifold of this invention is designed to provide a selected number of liquid bottles, chambers or cylinders and corresponding vapor bottles, chambers or cylinders connected by an atomizer fitted with an internal pressure-regulated check valve, to facilitate an appropriate ratio of gas to liquid in the system. After filling of the liquid cylinder or cylinders is completed according to the method of this invention, the customer or end-user will draw gas from the vapor cylinder(s). When a predetermined volume of gaseous carbon dioxide has been used from these vapor cylinder(s) by the customer to create a predetermined pressure differential in the pressure actuated valve located in the atomizer, the pressure-actuated valve will automatically open to facilitate a flow of additional liquid carbon dioxide into the atomizer. This liquid carbon dioxide rapidly expands into a gas and enters the vapor cylinder(s), in order to refill the vapor cylinder(s). The gas evolution process continues in the atomizer until the preselected pressure differential at the pressure actuated valve has been equalized and the pressure actuated valve then closes. A primary feature of the carbon dioxide fill manifold and method of this invention is the capacity for refilling both the liquid cylinder(s) and the vapor cylinder(s) without disconnecting these vessels from the supply and service lines, respectively. Since the liquid cylinder (s) and vapor cylinder(s) are filled by volume instead of by weight, the need to transport, handle and weigh the various carbon dioxide-containing vessels is eliminated.
A common method of providing an end-user such as a carbonated drink dispensing apparatus with carbon dioxide gas involves the use of high pressure containers, bottles or cylinders which are manufactured in various sizes, typically 20 and 50 pound quantities, wherein the weight designation refers to the weight of the carbon dioxide in the cylinders at full capacity. These cylinders are typically filled by weight instead of volume, since a portion of each cylinder (approximately 32%) must be reserved for expansion of the carbon dioxide into the vapor phase, in order to maintain an appropriate volume of liquid at a desired pressure. The problem of furnishing cylinders of uniform weight and carbon dioxide volume is amplified by the fact that there is no uniform weight or tare among the cylinders themselves. The cylinders are typically filled by placing them on a scale and charging them with liquid carbon dioxide until the desired weight of liquid carbon dioxide is injected therein. Accordingly, the carbon dioxide supplier must periodically interrupt the customer supply, in order to exchange a full vessel for the empty one, using this system. The empty cylinders must then be transported to a warehouse for weighing and refilling and the cycle is repeated. Expansion of a small amount of the carbon dioxide liquid into the gas phase exerts the necessary vapor pressure to maintain a proper gas-liquid balance in these cylinders, to assure proper dispensing of carbon dioxide gas to the end-user. These conventional carbon dioxide supply cylinders are typically equipped with a pressure disc which is designed to rupture if the pressure inside the cylinder rises beyond a specified level. Overfilling, that is, charging liquid carbon dioxide into that portion of the cylinder which is normally reserved for gas expansion purposes, will sometimes cause this disc to burst, an occurrence which is both dangerous and wasteful.
1. Description of the Prior Art
Various types of liquid and gaseous vapor-containing and handling systems are well known to those in the art. A "Fluid Medium Storing and Dispensing System" is detailed in U.S. Pat. No. 2,412,613, dated Dec. 17, 1946, to H. C. Grant, Jr. The patent details one or more receptacles or containers for storing a high-pressure fluid medium such as liquified carbon dioxide. Further included is a fluid medium retaining and releasing apparatus associated with each of the containers, which apparatus is adapted to be operated by the fluid medium from one or more containers in the system. A suitable actuating device which is operable by a relatively small force for initiating simultaneous release of the fluid medium from one or more of the containers, is also provided U.S. Pat. No. 2,492,165, dated Dec. 27, 1949, to D. Mapes, details a "System for Dispensing Fluids". The system includes multiple receptacles containing a fluid under pressure, apparatus provided in each of the receptacles for normally retaining a fluid therein, which apparatus operates to release the fluid from the receptacles, delivery means into which the fluid may be delivered from all the receptacles and a fluid-actuated operating device for operating the retaining apparatus of each receptacle. Apparatus for conducting fluid from the delivery means to the operating apparatus with at least one of the receptacles is also provided. A "Pneumatic Installation" is detailed in U.S. Pat. No. 2,591,641, dated Apr. 1, 1952, to J. Troendle. The installation includes one or more sources of compressed air, one or more devices to be fed with compressed air for pneumatic control purposes, several compressed air reservoirs and conduits connecting the various elements to each other. U.S. Pat. No. 3,760,834, dated Sept. 25, 1973, to David E. Shonerd, et al, details a "Reservoir for Pressurized Fluids". The reservoir includes multiple, straight tubes located in side-by-side relationship and surrounded by a single, elongated tube of substantially less diameter which is helically wound about the straight tubes to define a reservoir for pressurized natural gas. The helically-wound tube serves both as a protective covering and a strengthening structure for the straight tubes. The straight tubes and helically-wound tubes may be interconnected by suitable manifolding and a fill opening is provided for storing pressurized fluid therein. U.S. Pat. No. 1,062,343, dated May 20, 1913, to James H. Mahoney, details an "Apparatus for Dispensing Carbonated Beverages" such as beer, which includes a mechanism for reducing gas pressure while dispensing the liquid, to prevent undue foaming. U.S. Pat. No. 2,363,200, dated Nov. 21, 1944, to P. B. Pew, et al, details an "Apparatus for Dispensing Gas Material". The apparatus includes a system having an arrangement for storing and gasifying relatively large quantities of liquified gas such as liquid oxygen, in order to service large instantaneous demands. An "Apparatus and Method for Filling Gas Storage Cylinders" is detailed in U.S. Pat. No. 2,469,434, dated May 10, 1949, to O. A. Hansen, et al. The patented invention includes a mobile unit which includes a transport truck having a tailgate adapted to provide a temporary station for gas storage containers which are to be evacuated and filled with a gas material such as oxygen, in the gas phase. Suitable equipment is also provided on the truck for first evacuating and then charging the containers at the temporary station from a source such as a container in the liquid phase, which source is also mounted on the truck, together with the necessary apparatus for converting the gas material from the liquid to the gas phase. U.S. Pat. No. 2,479,070, dated Aug. 16, 1949, also to O. A. Hansen, details an "Apparatus for and Method of Dispensing Liquified Gases". The apparatus includes a pair of pressure containers for storing liquified gases, pressure regulating apparatus for maintaining the pressure in the containers above a predetermined value, a liquid line extending externally of the containers, with a heater provided in the liquid line and a pressure sensitive valve connected to the containers for controlling the flow of liquid in the containers. An "Apparatus for Storing and Dispensing Liquified Gases" is detailed in U.S. Pat. No. 3,093,974, dated Jun. 18, 1963, to C. E. Templer, et al. The apparatus includes a storage container for storing and dispensing a liquified gas, a liquid withdrawal pipe opening at a point near the bottom of the container and extending through the top thereof and a liquid feed line connecting the liquid withdrawal pipe to one end of a pressure raising coil located below the level of the bottom of the container. Further included is a vapor feed line connecting the other end of the pressure raising coil with the vapor space of the container through an automatic valve which is arranged to open when the pressure in the container falls below a predetermined value. A jacket surrounding that part of the liquid feed line above the level of the container, is also provided, the jacket having a connection to the liquid withdrawal pipe through a valve arranged to maintain a pressure drop between the liquid feed line and the jacket and the liquid service connection. A "Liquid Cylinder System" is detailed in U.S. Pat. No. 3,392,537, dated Jul. 16, 1968, to R. C. Woerner. The patent is directed to a distribution system for a vaporizable liquid, in which the liquid is stored in individual storage containers and is dispensed under pressure. A pressurizing system is associated with at least one of the storage containers to maintain a desired pressure in the system. U.S. Pat. No. 3,712,073, dated Jan. 23, 1973, to Edwin M. Arenson, details a "Method and Apparatus for Vaporizing and Superheating Cryogenic Fluid Liquid". The apparatus includes a closed vessel for heating medium liquid such that portions thereof are continuously vaporized. The stream of cryogenic fluid to be vaporized and superheated is passed through a heating coil disposed within the vessel and in heat exchange relationship with both the liquid and vapor portions of the heating minimum, so that the cryogenic fluid is vaporized and superheated to a desired level and the vaporized heating medium is continuously condensed and returned to the liquid portion thereof. U.S. Pat. No. 3,990,256, dated Nov. 9, 1976, to Walter G. May, et al, details a "Method of Transporting Gas", which method includes pumping liquified natural gas for a predetermined portion of the desired distance, applying processes in which the refrigeration value of the gas is utilized and the high boiling point components are separated, and subsequently vaporizing the remaining liquid prior to transporting the vapor by pipeline in the gaseous phase. U.S. Pat. No. 4,321,796, dated Mar. 30, 1982, to N. Kohno, details an "Apparatus for Evaporating Ordinary Temperature Liquified Gases". The apparatus includes an ordinary temperature liquified gas storing vessel, an evaporating chamber for evaporating a liquified gas and a liquid level detecting chamber for detecting the liquid level in the evaporating chamber. The detecting chamber is disposed between the storage vessel and the evaporating chamber and the liquid outlet from the storage vessel and detecting chamber are connected by conduit equipped with a liquid pressure reducing valve. The bottom of the detecting chamber and the liquid inlet to the evaporating chamber are connected by a liquid conduit and the respective gas outlets from the detecting chamber and the evaporating chamber are connected to a gas warming chamber. A "Carbonated Beverage Storage and Dispensing System and Method" is detailed in U.S. Pat. No. 4,683,921, dated Aug. 4, 1987, to Timothy A. Neeser. The system employs separate tanks for carbon dioxide and syrup and mixing occurs during dispensing. For each type of syrup there are preferably two syrup supply tanks and each syrup supply tank may be selectively connected to either a syrup filling source or to a sanitizing system for cleaning the tank. The system allows one of the syrup supply tanks to be sanitized or refilled, while the other supplies syrup for dispensing, thus allowing uninterrupted beverage service.
It is an object of this invention to provide a carbon dioxide fill manifold which is designed to provide an end-user with a substantially uninterrupted supply of carbon dioxide gas, while at the same time eliminating the necessity for transporting individual conventional bottles, containers or cylinders for refilling purposes.
Another object of the invention is to provide an on-site carbon dioxide refilling apparatus characterized by a fill manifold for connecting liquid and gaseous carbon dioxide cylinders and a method for automatically transferring the liquid carbon dioxide from the liquid cylinders to the gaseous cylinders where it is vaporized and dispensing the gaseous carbon dioxide to an end user, wherein the quantity of the gas distributed is determined by volume, rather than by weight.
Yet another object of this invention is to provide a new and improved carbon dioxide fill manifold which is designed for on-site use to facilitate connection of multiple liquid chamber bottles and companion vapor chamber bottles using a pressure-actuated atomizer, wherein an end-user or customer is supplied with a substantially uninterrupted source of carbon dioxide gas at a desired pressure.
Another object of the invention is to provide a carbon dioxide fill manifold which includes an atomizer containing a pressure actuated check valve to periodically automatically vaporize a charge of liquid carbon dioxide from a pair of liquid carbon dioxide storage bottles or cylinders connected to the atomizer for storage in a single gaseous carbon dioxide storage bottle also connected to the atomizer and dispensing in the gaseous phase to an end-user.
Still another object of this invention is to provide a carbon dioxide fill manifold which is characterized by a fill line valve and service line valve constructed from high pressure material and connected to a vaporizer or atomizer, connection ports for connecting a selected number of liquid chambers or cylinders and vapor cylinders to the atomizer and a pressure actuated check valve provided in the atomizer between the liquid and gas cylinder connection ports, wherein the total volume of the vapor cylinders represents approximately one-third of the total volume of the liquid chambers and gas cylinders and liquid carbon dioxide is introduced into the fill line to fill the liquid chambers and the liquid carbon dioxide is periodically vaporized into gaseous carbon dioxide in the atomizer responsive to a selected pressure differential across the atomizer, for dispensing to a customer.
Still another object of this invention is to provide a new and improved carbon dioxide fill manifold and method for storing liquid and gaseous carbon dioxide and dispensing carbon dioxide gas to a customer or end-user on a volume, rather than a weight basis and thereby eliminating the necessity of using multiple conventional individual carbon dioxide bottles or cylinders which must be periodically returned to a plant and refilled.
Another object of the invention is to provide a method of storing liquid and gaseous carbon dioxide and dispensing the gaseous carbon dioxide to a customer on demand, which method includes the steps of charging the liquid carbon dioxide into a pair of liquid chambers, allowing the liquid carbon dioxide to flow from the liquid chambers into an atomizer responsive to a selected pressure differential across the atomizer and vaporizing the carbon dioxide for storage in a gaseous chamber.